More than 115 million people and more than 48 million buildings live in U.S. counties classified as having high wildfire risk, according to the US Forest Service Wildfire Risk to Communities update. Preparedness data also shows a gap between what residents consider effective and what they have completed, especially for renters and structural improvements.
Table of contents
- Wildfire exposure in the United States
- Home-hardening measures residents report
- Defensible space and vegetation actions
- What residents believe works
- Education, incentives, and motivation
- Fire-department and jurisdiction preparedness
- Preparedness distances, alerts, and ignition pathways
Wildfire exposure in the United States
The US Forest Service Wildfire Risk to Communities update reports that more than one-third of the U.S. population, or more than 115 million people, live in counties with high wildfire risk. More than 48 million buildings, about one-third of all structures, are in those high-risk counties. These are population and structure exposure figures, not forecasts of how many homes will burn.
The US Forest Service Assessment of Community Wildfire Exposure uses a western U.S. model to estimate future exposure. It estimates that 1,812 communities could be significantly impacted by future wildfires, defined in the study as more than one structure exposed per year on average. Ignitions on national forest lands are expected to affect 516 of those communities.
The same assessment estimates that ignitions on all lands expose 19,400 structures to wildfire per year on average. Ignitions on national forest lands account for about 4,000 of those structures, or 21% of the total. The modeled figures describe average annual exposure in the study area; they are not a prediction for any single year or property.
Home-hardening measures residents report
The NFPA Wildfire Mitigation for Homes Stakeholder Research shows how often residents reported particular structural features. Fifty-five percent said their property already had dual-pane and tempered-glass windows. Forty-eight percent said they had noncombustible material or no fencing within 5 feet of the house, and 48% said they had metal mesh screens on vents, gutters, and the underside of eaves.
Fire-resistant siding was reported by 47% of residents, fire-resistant landscaping by 45%, and a fire-resistant roof assembly by 38%. Across the survey, 85% of homes had at least one structural mitigation measure. However, only 36% had most structural measures, defined as four to six measures.
The broader resident results show the difference between having some protection and completing several actions. Sixty-five percent of general residents had taken at least one structural mitigation action, while 46% had implemented at least two. Among homeowners, 35% had performed zero structural mitigation measures themselves, while 24% had performed four to six themselves.
Renters reported a substantially different level of visibility or coverage. Only 24% either lived on properties with at least one structural measure or were unsure whether any existed. Seventy-six percent reported no structural mitigation on the property. These renter figures describe reported property conditions and uncertainty in the NFPA resident survey; they do not establish that every rental property lacked a specific feature.
| Structural measure or result | Resident-reported share |
|---|---|
| At least one structural mitigation measure on the home | 85% |
| Dual-pane and tempered-glass windows | 55% |
| Noncombustible material or no fencing within 5 feet | 48% |
| Metal mesh screens on vents, gutters, and eaves | 48% |
| Fire-resistant siding | 47% |
| Fire-resistant landscaping | 45% |
| Fire-resistant roof assembly | 38% |
| Most structural measures, four to six | 36% |
Source: NFPA Wildfire Mitigation for Homes Stakeholder Research.
Defensible space and vegetation actions
Vegetation-related preparation was more common than structural work in the NFPA resident survey. Ninety-one percent of residents had performed at least one vegetation mitigation action. Sixty percent had completed four to six vegetation mitigation actions, and 26% had completed all six. Among renters, 44% had completed at least one vegetation mitigation action.
The survey measured several specific actions. Residents reported that removing vegetation and flammable materials within 5 feet of the house was effective at a rate of 91%. Removing needles and leaves from roofs and gutters was rated effective by 88%, while removing excess vegetation around shrubs and trees was rated effective by 87%.
Relocating firewood or lumber at least 30 feet from the house was considered effective by 85% of residents. Thinning and pruning trees so they do not touch each other was considered effective by 84%. These perception figures do not mean the action was completed; they measure what respondents believed would help.
CAL FIRE Get Ready says defensible space should extend 100 feet around the home. It also says annual grass should be cut or mowed to a maximum height of 4 inches and combustible materials should be kept 30 feet away from the home. The IBHS Near-Building Noncombustible Zone reference describes historically used zones of 0 to 30 feet and 30 to 100 feet, or to the property line.
IBHS and NFPA have advocated since 2011 for dividing the 0-to-30-foot area into 0 to 5 feet and 5 to 30 feet. IBHS recommends a 0-to-5-foot noncombustible zone around a building, including attached decks. IBHS Wildfire Adaptation Roadmaps calls this 0-to-5-foot home ignition zone one of the most critical actions for suburban wildfire protection.
What residents believe works
The NFPA survey found high perceived effectiveness for both vegetation and structural measures. Fire-resistant roof assembly was considered effective by 83% of residents, fire-resistant landscaping by 82%, and fire-resistant siding by 81%. Metal mesh screens on vents, gutters, and eaves were rated effective by 80%, while dual-pane and tempered-glass windows were rated effective by 79%.
These beliefs broadly exceeded the reported prevalence of several measures. For example, 83% considered a fire-resistant roof assembly effective, but 38% reported having one. Similarly, 81% considered fire-resistant siding effective, while 47% reported that feature. The comparison is descriptive: the survey results do not establish why the shares differ or whether a respondent’s property met a particular construction standard.
The gap also appears in awareness of financial support. Seventy-eight percent of residents said none of the listed mitigation incentives were applicable to their property. Only 3% were aware of wildfire mitigation incentive programs, while 97% were unaware that such programs exist.
Education, incentives, and motivation
Only 24% of residents had received education on defensible space or home hardening in the NFPA Wildfire Mitigation for Homes Stakeholder Research. Residents who received mitigation education were more likely to report four to six structural measures: 51% did so, compared with the corresponding group without that education. Among educated residents, 89% reported four to six vegetation measures.
Incentives were also associated with higher reported completion. Residents who received at least one incentive were more likely to have four to six structural mitigation measures, at 57%, compared with 31% among residents with no incentives. They were also more likely to have four to six vegetation mitigation actions, at 94%, compared with 69% among residents with no incentives. These are survey associations, not proof that incentives caused the difference.
Motivation was high when mitigation was required by law or merely suggested. Eighty-four percent of residents were somewhat or very motivated to learn more when mitigation was required by law, and 84% were similarly motivated when it was suggested. Conversely, 16% said they were not too or not at all motivated when mitigation was required by law.
Residents most often valued their property’s convenient location, cited by 57%. Neatness or maintained appearance was cited by 37%, privacy by 33%, naturalness by 30%, and openness by 28%. These property values may help explain why preparedness guidance that protects both safety and appearance can reach different audiences.
Fire-department and jurisdiction preparedness
The NFPA survey included 71 fire-department respondents and 30 government officials. Among fire-department respondents, 82% said their department provides wildfire hazard or risk assessments on private property, while 18% do not. Seventy-two percent said their department has community wildfire protection programs, 70% has evacuation planning programs, and 65% has evacuation preparedness programs.
Vegetation management assistance was reported by 52% of fire departments. Disposal programs for cleared fuel and vegetation debris were reported by 41%, and home-hardening or structure-modification programs by 35%. Ninety-nine percent said their department does not provide equipment-lease programs for wildfire mitigation.
Communication programs were common but varied by audience. Eighty percent of fire departments provide communication or education about wildfire risk to properties, and 76% provide it to communities. Sixty-nine percent provide communication or education about safety, health, and life risks and about mitigation implementation guidance. Forty-eight percent provide communication about mitigation policies and regulations or ordinances.
Reported outreach included direct activities such as home visits, assessments, or webinars from 45 departments. Social media outreach was reported by 47 departments, and mailing outreach by 29. Nine respondents reported no plans to increase or start any of the listed outreach programs.
Planned increases were reported by 11 respondents for publications on mitigation measures aimed at planners, contractors, or insurance companies. Five planned more publications for communities, and five planned more hands-on defensible-space and fire-safety workshops and meetings. Four planned more public workshops on wildfire risk and mitigation actions, while four planned more demonstration projects. Three planned more demonstration homes or gardens, three planned more classroom curricula or school resources, one planned more general publications, and one planned more fire-department open-house opportunities.
At the jurisdiction level, 67% communicated wildfire risk to safety, health, and life, while 63% communicated risk to communities, according to the US Forest Service and NFPA report source line summary. In the NFPA government-officials survey, 49% of jurisdictions said they conduct inspections and enforcement of wildfire-related regulations and ordinances.
Preparedness distances, alerts, and ignition pathways
FEMA Wildfire Evacuation Outreach Materials says residents can receive wildfire alerts for a chosen ZIP code or within 30 miles. FEMA Wildfire Actions says the FEMA app provides real-time National Weather Service alerts for up to five locations nationwide. Ready.gov Kids Wildfires says fire weather watches can cover the next 12 to 72 hours of dangerous fire-weather conditions and that a wildfire can be followed by an evacuation notice telling people it is important or mandatory to leave.
FEMA says a fire-resistant zone should be free of leaves, debris, or flammable materials for at least 30 feet away from the home if possible. IBHS recommends the more specific 0-to-5-foot noncombustible zone, including attached decks. IBHS says an attached deck can spread intense fire toward the home through extreme heat, direct flame contact, and burning embers.
NIST Structure Hardening for Embers says embers can arrive miles ahead of the wildfire front and ignite homes and property. NIST How Fire Spreads in the WUI identifies three structure-ignition pathways: ember ignition, vegetative-fire ignition, and radiant exposure.
The US Forest Service Science Findings report on a Pacific Northwest study area found that human activity caused about 58% of ignitions. Human activities caused 73% of ignitions west of the Cascades and 48% east of the Cascades. Recreation accounted for 32% of ignitions and open debris burning for 24% in that study. Those percentages describe the study area and its measurement context, not every wildfire region.
IBHS reports that wildfire activity burned 5 million acres in 2007 and almost 10 million acres in 2017. Its Wildfire Adaptation Roadmaps recommends a Class A fire rating for roof material when re-roofing. Together, the exposure, ignition, and resident survey figures show why preparedness includes both routine property work and an evacuation-alert plan.